This invention relates to a temperature sensing and frying time cycle adjusting electronic circuit for use with a fat fryer.
Many restaurants and food services use deep fat fryers for preparing French fried potatoes, fried chicken, donuts, and other fried foods. These frying mechanisms include means for heating a fat or oil in a container. Food to be fried is then placed in the container for a predetermined frying time. One or more timing mechanisms are frequently attached to the apparatus for timing the frying cycle of the food to be fried. Such apparatus also frequently contains some sort of overtemperature control mechanism for preventing the fat or oil from becoming too hot. Preventing the frying fat or oil from overheating decreases the likelihood of fire, increases the useful life of the fat or oil used, and helps control the temperature at which the food is fried, thereby preventing burning or overheating of the food itself during the frying cycle.
Such systems generally employ mechanical or electrical timers to time the frying cycle and temperature sensors mounted in intimate contact with the heated container or mounted in probes immersed in the frying fat or oil to sense fat temperature. The temperature sensor mechanism generally operates independently of the timer mechanism. Typically, fat in such systems must reach a fairly constant temperature before the system is put to use. It may take the equivalent of several frying time cycles for the fat temperature to stabilize and much time may be required before any food is fried. However, by incorporating the temperature sensing and timing functions in a single electrical system, the apparatus required for achieving the two necessary functions of timing and temperature sensing can be simplified. A significant advantage which is made possible by combining the timing and temperature sensing functions is that the timing cycle can be varied with changes in the fat temperature. For example, if the fat temperature increases during a frying cycle, it would be possible to automatically decrease the length of the timing cycle to compensate therefor. Conversely, if the fat temperature should decrease, the timing cycle would automatically increase in length.